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1.
Determining ontogenic diversity in vegetables, in general or Brassicas in particular, regarding the bioactive content, is an interesting task since the most promising Brassicaceae foods could have the highest nutritional and health-promoting properties. Therefore, vitamin C, phenolic compounds, glucosinolate content, and total antioxidant capacity were evaluated in commercial cultivars of broccoli (Brassica oleracea var. italica; cv. Nubia, cv. Marathon and cv. Viola) seeds and during the sprouting period. Vitamin C was not detected in dormant seeds and its content increased with the germination, reaching values ranging from 53 (cv. Nubia) to 64 (cv. Marathon) mg/100 g FW, at the end of the monitored period (14days). The total glucosinolate content in seeds and 3-day-old sprouts was higher in cv. Marathon (1005 and 556 mg/100 g FW, respectively), however cv. Viola sprouts registered the highest glucosinolate content 7 and 14 days after sowing (235 and 208 mg/100 g FW, respectively). Aliphatic glucosinolates were more affected by genetic factors than the indolic glucosinolates, being glucoraphanin the predominant glucosinolate in cv. Nubia and cv. Marathon, whereas glucoiberin was the major glucosinolate in cv. Viola. The flavonoid and total phenolic content was significantly higher in cv. Viola. Also, seeds of this cultivar showed the highest antioxidant capacity (2.7 mg Trolox/g FW).  相似文献   

2.
The fruit quality characteristics, phenolic compounds and antioxidant capacities of 24 sweet cherry (Prunus avium L.) cultivars grown on the mountainsides of the Etna volcano (Sicily, Italy) were evaluated. High-performance liquid chromatographic methods were used to identify and quantify sugars, organic acids and phenolics. A total of seven phenolic compounds were characterised as hydroxycinnamic acid derivatives (neochlorogenic acid, p-coumaroylquinic acid and chlorogenic acid) and anthocyanins (cyanidin 3-glucoside, cyanidin 3-rutinoside, pelargonidin 3-rutinoside and peonidin 3-rutinoside). The total anthocyanin content ranged from 6.21 to 94.20 mg cyanidin 3-glucoside equivalents/100 g fresh weight (FW), while the total phenol content ranged from 84.96 to 162.21 mg gallic acid equivalents/100 g FW. The oxygen radical absorbance capacity (ORAC) assay indicated that fruit of all genotypes possessed considerable antioxidant activity. The high level of phenolic compounds and antioxidant capacity of some sweet cherry fruits implied that they might be sources of bioactive compounds that are relevant to human health.  相似文献   

3.
The physico-chemical properties of some tropical fruits (pineapple, orange, grape, mango and lemon) were analyzed and compared with those of cashew apple. Cashew apple juice was found to contain the highest amount of vitamin C (203.5 mg/100 ml) of edible portion. Orange, grape, pineapple, mango and lemon contained average values of 54.7 mg, 45.0 mg, 14.70 mg, 30.9 mg and 33.7 mg vitamin C per 100 ml of juice respectively. Obviously, cashew apple juice contains almost four times the amount of vitamin C in the popular citrus fruits and more than four times as much vitamin C as in other fruits. Hence, when cashew apple was blended with other tropical fruits it boosted their nutritional quality. On the other hand, these fruits improved the acceptability of cashew juice in terms of taste and flavour. The blends, even though significantly different (P <0.05) in taste, colour and mouthfeel, were all acceptable to consumers with no significant difference (P>0.05) in overall acceptability. Received: 16 August 1999 / Revised version: 2 November 1999  相似文献   

4.
Effects of enzymatic and non-enzymatic juice pressing on key orosensory and chemical quality factors of blackcurrant juices were studied in laboratory scale using berries of five different cultivars (Mortti, Mikael, Marski, Ola and Breed15). Enzymatic processing increased the juice yield by 10–22% and the content of various phenolic compounds in juice by 4–10-fold as compared to the non-enzymatic process. Higher intensity of the mouth-drying astringency of the enzyme-aided juice was the most significant orosensory difference between the processes. Juices of different blackcurrant cultivars varied in sweetness, sourness and bitterness. The most intensive sensory attributes of the juices were sourness and puckering astringency regardless of processing method. They correlated positively with each other and were contributed by acid content and pH. In enzyme-aided juices, the contents of flavonol glycosides and hydroxycinnamic acids were associated with mouth-drying astringency, and sugar/acid ratio correlated with sweetness. These correlations were less clear in non-enzyme juices possibly due to lower content of phenolic compounds and the high content of pectin.  相似文献   

5.
为研究不同水煮时间对青椒中VitC含量的影响,利用高效液相色谱法测定新鲜青椒中VitC的含量,并在相同条件下,将青椒煮沸不同时间后测定青椒中VitC的含量,比较两者结果。结果表明:煮沸时间的不同,对青椒中VitC含量的影响不同,加热时间越长,青椒中VitC的含量损失越多,水中VitC的含量相对越多。  相似文献   

6.
The effects of different initial in-package O2 and CO2 concentrations (2.5 kPa O2 + 7 kPa CO2, 10 kPa O2 + 7 kPa CO2, 21 kPa O2, 30 kPa O2 and 70 kPa O2) on peroxidase activity, vitamin C content, total phenolics and antioxidant capacity of fresh-cut ‘Piel de Sapo’ melon have been investigated for 14 days at 4 °C. The radical scavenging activity of fresh-cut melon strongly increased after 9 days storage related to a synthesis of phenolic compounds, especially under 2.5 kPa O2 + 7 kPa CO2 atmospheres. Low O2 levels best maintained vitamin C and phenolic content during the storage. However, stressful too-low O2 and high CO2 levels induced an important increase of peroxidase activity under 2.5 kPa O2 + 7 kPa CO2 atmosphere, which was directly related to changes of vitamin C throughout storage. Therefore, 70 kPa O2 atmospheres are proposed to prevent anaerobic conditions during storage of fresh-cut melon and thus, reduce wounding stress and deteriorative changes related to high peroxidase activity in tissue.  相似文献   

7.
Deterioration of stored rye samples was studied at different moisture contents and temperatures. Germination, presence of visible and invisible microflora, and free fatty acid values (FAV) were determined for samples at 10.0, 12.5, 15.0 and 17.5% moisture content (wet mass basis) stored at 10, 20, 30 and 40 °C for 16 weeks. Results of deterioration at constant moisture content (case 1) were compared with previously reported results for deterioration under declining moisture content (case 2). Germination rate was almost the same for all the moisture content samples stored at 10 °C for both cases, but a significant decrease was observed at other temperatures with high moisture content. Fatty acid values remained similar in both cases when rye was stored at 10 and 20 °C, whereas at 30 and 40 °C, FAVs of the rye samples in which the moisture content was maintained were high and increased with an increase in temperature and moisture content. Visible mould appeared early in the samples whose moisture content was maintained. Penicillium spp. and Aspergillus glaucus group were the predominant fungal species present in both the cases throughout the study. The rate of deterioration was significantly different between the two cases.  相似文献   

8.
Three different cultivars of drought, salt and boron (B) tolerant Opuntia ficus indica (Cactus pear) were grown in poor-quality agricultural drainage sediment high in salt, B and selenium (Se) that originated from the Westside San Joaquin Valley. Nutritional contents were then measured in these Cactus pear fruit (purple, red, or orange-coloured), and vegetative cladodes (modified stem-like leaves) compared to the same cultivars grown adjacent on a low saline sandy loam soil. After harvesting fruit and cladodes, the mineral nutrients, chemical speciation of Se, total phenolics, vitamin C and antioxidant status were analyzed. The results demonstrated positive nutritional changes in both cladodes and fruit within the Cactus pear cultivars when grown on agricultural drainage sediment compared to those grown on normal soil. Under these conditions Cactus pear plants contained nutraceutical qualities and represent a useful anticarcinogenic Se-enriched chemotherapeutic food crop for providing advanced dietary seleno-pharmacology in order to help fight human diseases.  相似文献   

9.
10.
We have investigated the diversity for composition in seven eggplant (Solanum melongena) cultivars of the Occidental type. The results show that, with the exception of moisture content and pH, there is a wide diversity for all the analysed traits. Protein content was variable, but generally low. The content in available carbohydrates ranged between 2.99 and 4.19 mg 100 g?1, and the main soluble sugars were glucose and fructose. The fibre content was the most variable trait. In all cases, the dehydroascorbic acid content was higher than the ascorbic acid content. Total phenolics content was on average thirty‐nine‐fold higher than vitamin C content. Multivariate analysis showed that accessions from the black and striped groups presented a similar composition profile, while the white and pickling fruits were very distinct. The pickling eggplant H11 is identified as the best source for improving the nutritional and functional properties of Occidental eggplants.  相似文献   

11.
The polyphenols and total antioxidant activities of five apple cultivars, grown by organic and conventional agricultural methods in neighbouring farms, were determined and compared. Total polyphenols in the whole fruit and in the peel were determined by the Folin-Ciocalteu method, and the total antioxidant activity was determined by three established methods, diphenyl picrylhydrazyl (DPPH), azinobis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and ferric reducing/antioxidant power (FRAP). Polyphenolic content for the whole fruit was in the range of 80–196 and for the peel 165–400 (mg Gallic Acid Equivalent (GAE)/100 g fresh weight) for both types of agricultural practices. Antioxidant activities of fruit extracts were also relatively similar and well correlated to their polyphenolic content. High-performance liquid chromatography (HPLC) analysis of the most important polyphenolics (chlorogenic acid, catechin, epicatechin, procyanidin B1 and B2, cyaniding 3-galactoside, phloridzin, quercetin 3-galactoside and quercetin 3-arabinoside) also showed that concentrations do not differentiate significantly between the organic and conventional apples. Statistical significance of differences in antioxidant activities among the same cultivars was relatively small (flesh + peel or peel only) for both types of apples. These results indicate that organic apples do not present higher antioxidant or nutritional value compared with conventionally grown ones, as far as polyphenolic content and total antioxidant activities are concerned.  相似文献   

12.
Arils from six pomegranate (Punica granatum L.) cultivars obtained from various sites from the Mediterranean region of Turkey were evaluated for their chemical and antioxidant properties. These properties included total phenolics (TP), total monomeric anthocyanins (TMA), soluble solids (TSS), titratable acidity (TA), individual sugars and organic acids. Antioxidant capacities of arils were determined by both the ferric reducing antioxidant power (FRAP) and trolox equivalent antioxidant capacity (TEAC) assays. The antioxidant capacities averaged 5.60 and 7.35 mmol TE/l by the TEAC and FRAP methods. Variability among cultivars was greatest for TMA content (CV 132%); individuals ranged from 6.1 to 219 mg cy3-Gluc l−1. TP means averaged 1507 mg GAE/l. Levels of FRAP, TEAC, TP, and TMA were strongly correlated (r = 0.82–0.96). The major sugars were fructose (6.4 g/100 ml) and glucose (6.8 g/100 ml), the major acids were citric (1.78 g/100 ml) and malic (0.12 g/100 ml).  相似文献   

13.
The aim of this study was to evaluate the effects of high hydrostatic pressure treatment at three pressure levels (300, 400 and 500 Mpa) on the functional and quality characteristics of Aloe vera gel including vitamin C and E, aloin, minerals, phenolic content and antioxidant activity. The results show that HHP exerted a clear influence on minerals content, vitamin C and E content, antioxidant activity, total phenolic and aloin content. After 35 days of storage all treated samples presented a decrease in mineral content, except for phosphorus. Total phenolic content and vitamin C and E content decreased at high pressures (500 MPa), while all pressurised samples showed a higher antioxidant activity and aloin content than untreated sample after 35 days of storage. The maximum values of antioxidant activity and aloin were 6.55 ± 1.26 μg/ml at 300 MPa and 24.23 ± 2.27 mg/100 g d.m. at 400 MPa.  相似文献   

14.
Optimisation of the germination process of different cultivars of broccoli (Brassica oleracea var. italica cv. Lucky, cv. Tiburon and cv. Belstar) and radish (Raphanus sativus cv. Rebel and cv. Bolide) seeds in relation to the content of glucosinolates (GLS), vitamin C and total antioxidant capacity was carried out in order to maximise the health-promoting properties of Brassica sprouts. The content of total and individual GLS varied between species, among cultivars, and germination time. Glucoraphanin in broccoli and glucoraphenin in radish were the predominant GLS in raw seeds (61–77 and 63–129 μmol/g DM, respectively) and, although their content decreased during germination, they were maintained in rather large proportions in sprouts. Vitamin C was not detected in raw seeds and its content increased sharply in broccoli and radish sprouts (162–350 and 84–113 mg/100 g DM, respectively). Raw brassica seeds are an excellent source of antioxidant capacity (64–90 and 103–162 μmol Trolox/g DM in broccoli and radish, respectively) and germination led to a sharp increase. Germination of broccoli cv. Belstar and radish cv. Rebel for 4 days provided the largest glucoraphanin and glucoraphenin content, respectively, and also brought about large amounts of vitamin C and antioxidant capacity.  相似文献   

15.
 This study confirmed the significant role of phenolics in the dormancy of cereal caryopses. Investigations were conducted on two cultivars of wheat (Elena and Alba), rye (Amilo and Dańkowskie Złote), and triticale (Ugo and Bogo), with characteristic deeper or shallow dormancy, respectively. In germination studies, cultivars susceptible to sprouting (Alba, Dańkowskie Złote and Bogo) displayed higher germination percentages than those resistant to sprouting (Elena, Amilo and Ugo). The phenolic acid contents (i.e. free, liberated from soluble esters, and liberated from soluble glycosides) in caryopses were determined by an HPLC method. Caffeic, p-coumaric, ferulic and sinapic acids were the dominant phenolic acids detected. The majority of phenolic acids were found in the form of soluble esters. For all species examined, the levels of phenolic acids liberated from soluble esters and the total phenolic acid contents in caryopses showing shallow dormancy were higher than in those showing deeper dormancy. Slight differences in the UV spectra of extracts of phenolic compounds from caryopses showing shallow or deeper dormancy were noted. Received: 6 April 1999  相似文献   

16.
The influence was evaluated of four rootstocks (Ishtara, Mr. S 2/5, GF 677 and Barrier 1) and of harvesting time (early, middle, late) on the quality characteristics and nutritional value (vitamin C, phenols, carotenoids, total antioxidant capacity) of ‘Flavorcrest’ peach. The better rootstocks were Mr. S 2/5 (low-vigour) and Barrier 1 (high-vigour). In particular, Flavorcrest fruit on Mr. S 2/5 and on Barrier 1 rootstocks had higher antioxidant capacities and also higher phytochemical content, although fruits on Mr. S 2/5 were less firm.  相似文献   

17.
Total polyphenols, carotenoids and vitamin C were assessed in three different peaches cultivars (Prunus persica): ‘Luisa Berselli’ (LB), ‘Stark Earlyglo’ (SE) and ‘Maria Serena’ (MS). Total antioxidant capacity of fruits and plasma antioxidant activity after ingestion of fruits were determined as Trolox equivalent antioxidant capacity (TEAC) and as plasma total radical-trapping potential (TRAP) respectively. The amount of polyphenols, carotenoids and vitamin C resulted to be generally similar in the three cultivars. TEAC, measured from harvest to 7 days postharvest, resulted to be influenced mainly by vitamin C content, whereas polyphenols and carotenoids seemed to play a secondary role. Although TEAC was similar in the three cultivars, only LB significantly increased the TRAP in human plasma at 1, 2 and 4 h after ingestion of peaches. Sugar moiety, condensed and glycoside phenols are suggested to be involved in the higher effect on plasma TRAP of LB.  相似文献   

18.
The objective of this study was to evaluate the effect of the incorporation of spirulina on technological and nutritional quality of dried pasta. Wheat flour was substituted by spirulina biomass at three levels: 5, 10 and 20 g/100 g, and a sample without spirulina biomass was made as control. The technological quality was analyzed in terms of cooking properties and texture profile, while pasta surface was observed by confocal microscopy. In addition, protein content, in vitro protein digestibility, phenolic compound content and in vitro antioxidant activity were the major bio-functional characteristics measured. An in vitro starch digestion was performed in order to estimate the glycemic index. Only pasta with 20 g of spirulina / 100 g of flour did slightly modify technological quality parameters; microstructure studies revealed the impact of spirulina addition, resulting in a more heterogeneous surface. The glycemic index was not affected by the addition of spirulina. The incorporation of spirulina resulted in an increase of protein content; however, protein digestibility was reduced as microalgae content increased. Pasta with spirulina exhibited high phenolic compounds content and antioxidant activity compared to control pasta, which could be used to enhance the nutritional profile of the product.  相似文献   

19.
This work concerns the degradation of the nutritional compounds glucoraphanin (GR) and vitamin C (Vc), and the inactivation of the enzyme myrosinase (MYR) in broccoli (Brassica oleracea var. italica) during drying with air temperatures in the range of 30–60 °C. Dynamic optimization is applied to find the optimized temperature trajectories that minimize degradation and inactivation. Simulation and experimental results for optimized temperature trajectories are compared to constant inlet air temperature drying at 40 and 50 °C. The results show that with the optimized temperature trajectories the retention of GR, MYR and Vc improved significantly. Moreover, the experiments show that degradation and inactivation during drying is slower than expected from kinetic studies. The deviation is explained from the difference in the physical state of the samples used in the drying experiments, i.e. original plant tissue versus the grounded state of the plant tissue used in the experiments for the kinetic studies. The results indicate that besides temperature and moisture content the physical state is also an important aspect in the degradation of nutritional compounds and enzymes.  相似文献   

20.
The volatile composition and the nutritional value of Polyporus tenuiculus grown on supplemented and nonsupplemented wheat straw and willow sawdust were determined. Thirty‐nine volatile compounds were detected, including acids, esters, alcohols, hydrocarbons, aldehydes and ketones. The main volatile compound in all samples was 1‐octen‐3‐ol, with increasing levels in mushrooms cropped on supplemented substrate. In addition, several precursors of this alcohol were identified in lower percentages. Mushrooms grown on supplemented substrates showed lower fat (5.2–5.7%) and carbohydrate contents (48.2%) and higher protein content (22–22.5%). Fibre and ash contents showed some variations between types of substrates. Compared to other edible fungi, P. tenuiculus high fibre and protein contents point to this species as a healthy nutritional alternative of interest for the food industry. Moreover, the wide spectrum of volatile compounds of P. tenuiculus reveals great potential for biotechnological applications such as the production of “non artificial” mushroom flavour.  相似文献   

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